Container



Jan. 18, 1949. G, R, SPARKS ETAL 2,459,193

CONTAINER Filed Sep.. 15, 1944 INVENTOR. GEORGE R. SPARKS CARROLL G.KILLEN,JR

l emma 1.11. 1s, 1949 CONTAINER George R. Sparks, Asbury Park, andCarroll G. Rillen, Jr., Wanamassa, N. J.

Application September 13, 1944, SerialNo. 553,858 1 claim. (ci. 114-10(Granted under the act of March 3, 1883, as amended April 30, 1928; 3700. G. 757) The invention described herein may be manufactured and usedby or for the Government for governmental purposes, without the paymentto us of any royalty thereon.

This invention relates to containers and particularly containers forelectric and electronic apparatus and the like which require that theapparatus be hermetically sealed and that electrical leads pass throughthe container to connect the apparatus to a circuit.

The operation of sensitive electronic devices, such as meters, coils,rectiers and the like, is adversely affected by exposure to dampness,dust, oil and the elements, and it is therefore advisable tohermetically seal them within suitable containers, frequently of metal.To do so however poses the problem of providing satisfactory means ofbringing electrical leads through the containers without grounding themand without weakening the hermetic seal.

The problem has been complicated by the fact that present day use ofsuch apparatus, as in the arctic and the tropics and in air, land andwater vehicles, often subjects them to severe vibration, humidity, thecorrosive effects of salt water and saline atmosphere, the ravages oftropical bacteria and extremes of, and sudden fluctuations of, pressureand temperature,

Some of said devices operate under optimum conditions if maintained at apredetermined pressure, which may be above or below normal atmosphericpressure, or if hermetically enclosed in a gas filled chamber.

Some containers presently being used have several members joinedtogether with screws and depend upon some gasket material for hermeticsealing. These are unsatisfactory because the uneven pressure of thescrews ultimately results in rupture of the seal and vibration,humidity, temperature changes, etc. loosen the gasket material.

Other containers use a separate bushing of insulating material for eaclrlead. Such construction is usually expensive, it invites breakdown ofthe hermetic seal because there are a multiplicityA of places wherebreakdown might occur, the leakage paths between conductors are usuallyshort, and a large opening through which the apparatus may be passed forinstallation within the container is also necessary.

Some containers require complicated machinery or processes forhermetically sealing them. There is therefore a need for good containerswhich may be largely prefabricated and which may be easily andinexpensively sealed by the user.

It is, therefore, an object of the present invention to providecontainers which are hermetically sealed throughout and which will notbe adversely affected by dampness, dirt, oil, weather, temperature,vibration, bacteria, etc.

It is another object to provide means for suitably bringing leadsthrough such containers so that there is a high electrical resistancebetween each lead and other conducting parts.

It is also an object to make such containers so that the apparatus to behoused therein may be easily and expeditiously mounted therein and thecontainers may be easily sealed by the user,

It is a further object to make a type of container where the leadsthrough it will have good mechanical strength and wherein the electricalleakage paths between the leads and other electrical conducting partswill be extended.

Another object is to provide a container which will allow tuning orother electrical manipulation of the sealed unit.

It is another object to provide containers which are hermetically sealedso they may be evacuated, pressurized or gas impregnated.

Still another object is to provide a type of container constructionwherein the hermetic seal will be maintained even though two materials,having different coeiicients of expansion, such as metal and glass, areused, the construction being such as to allow some relative movementbetween the two materials.

Another object is to provide a container which may be largelyprefabricated and which may be easily and effectively hermeticallysealed when put into use. The nonmetal parts are therefore silvered orotherwise prepared for bonding in advance so that sealing may be readilyeifected when the container is about to be used.

Other objects will appear from the following specification and theappended drawings.

As used herein, the terminology lead-through conductor shall indicate aconductor which extends through a wall of nonconducting material of acontainer and is suitably hermetically bonded to said material, as byone of the conventional processes referred to herein.

'I'he objects aforesaid are accomplished primarily by using insulatingmaterial, preferably glass or some similar vitreous insulating material,for one or more large surfaces of a container, and by bringing the leadsthrough said material and bonding them to it. It is preferred to usesuch insulating material for at least one entire side or wall of acontainer. This facilitates the positioning and mounting of apparatuswithin the container. A suitable number of electrical lead-throughconductors are hermetically embedded or bonded into said unitary side orwall, so as to extend completely through it. Lead wires may-be connectedfrom the apparatus to the inner ends of the lead-through conductorsbefore said side orwall is put into place. The wall of nonconductingmaterial may then be Joined to the balance of the container by anysuitable hermetic .bonding means, it being preferred to use a solderseal. The remainder of the container may be of any conducting ornonconducting material which can be hermetically bonded to the wall ofinsulating material which holds the leads. Metal or glass or othervitreous insulating material are preferred, as they may be easily bondedto a wall of insulating material, such as already described.

The insulating material should be of a type which will withstand highthermal shock and which will have suflicient mechanical strength toenable it to sustain physical shock and vibration incident to thecontemplated usage of the apparatus.

Although the insulating material, such as glass, may be of a uniformthickness throughout and the lead-through conductors may passtherethrough and be bonded thereto, it is preferred to thicken thematerial at each place where a lead-through conductor is to pass throughit. said thickness being preferably accomplished by forming bothupwardly and downwardly extending protuberances in the material. Thisthickening of the insulating material and resultant lengthening of theconductor extending through it make for greater mechanical strength ofthe insulating material encircling the conductor and lessens thelikelihood of rupturing the bond between said material and theleadthrough conductor, due to bending or other manipulationr of theconductor outside the container. The protuberances also have the addedadvantage of causing a lengthening of the electrical leakage paths,along the surface of the insulating material, between the lead-throughconductor and other electrically conducting portions of the unit, suchas other lead-through conductors or parts of the container itself, if ofa conducting material. For additional mechanical strength of the wall ofinsulating material and to further increase the leakage paths, it isfound to be good practice to form ridges or headings in the insulatingmaterial, particularly about its periphery or a short distance intherefrom.

In the drawings, Figure 1 is a perspective view of the upper portion ofa container for an electronic device which is provided with severalleads and a built-in socket for an electronic tube.

Figure 2 is an enlarged vertical cross sectional view, along the line22, of the container of Figure 1. v

Figure 3 is a perspective view of a second type of container embodyingthe present invention, being illustrated as enclosing the coils of atunable transformer.

Figure 4 is a longitudinal cross sectional view of the container ofFigure 3.

Figure 5 is an enlarged fragmentary view of one of the lead-throughconductors of Figure- 4.

Figure 6 is a perspective view of a third form of container embodyingour-invention, and

Figure 7 is a longitudinal cross sectional view of the container ofFigure 6.

Referring now particularly to Figures 1 and 2, the container there showncomprisese a rectangular box i'l and a cover i3. The side walls il andthe bottom (not shown) of the box il are made up of sheet metal,contiguous edges being welded together. The top of the box ii is open,said opening being closed by the cover I3, when the container is putinto use. The upper peripheral portions of said side walls il about theopening are bent inwardly and then downwardly, at a small angle to saidvertical side walls, for a short distance, to form the short inner wallsi1, and then inwardly again to form the horizontally disposed anges i3.Said inner walls il and flanges i3 extend completely around the insideof the opening of the box i'l so as to form a supporting ledge for thecover i3.

Said cover I3 is formed of a single piece of glass and, when thecontainer is to be sealed, its entire peripheral edge is bonded to theinner surfaces of the inner walls I1, by means of solder 2i, is anyconventional manner as already mentioned. The said glass cover I3 isformed with an upwardly directed beading 23, which extends completelyabout its periphery. At several places the glass of the central area 2lof the cover I3 is thickened to form upwardly and downwardly extendingprotuberances 21. At each of these thickened places the glass is piercedby a vertically disposed, circular passage 28 through which passes alead-through conductor 30.

Each such conductor 30 is made up of a central metal rod 3i, surroundedby a tubular metal sheath 33, having a hood-like metal ilange 35 at itsupper extremity. The sheath 33 and the rod 2| are joined by solder (notshown) or other suitable means so as to be hermetically sealed togetherinto an integral unit. The inner surface of the hood-like flange 35 isbonded to the upper end of the upper protuberance 21 by means of solder2| as already mentioned.

At another place, in the central area 25 of the cover i3. the glass isformed into an upwardly protruding, flat topped, cylindrical mound 31,

" which is pierced by several vertical bores 39. The

upper end of each of said bores 38 terminates in a chamfered surface 4I.Positioned in said bores 39 are metal cups 43, their upper ends beingush with the upper surface of the mound 31 and their lower ends beingclosed and extending below the lower surface of the glass. Said cups 43are bonded to the chamfered surfaces 4I by solder 2| as alreadydescribed, the solder also being finished flush with the upper surfaceof the mound 31. The cups 43 are of a size and are relatively disposedso as to be receivable to the prongs of an electronic tube (not shown),said prongs being of the type having resilient means to eiect electricalcontact with the cups. Cups (not shown), which are themselves fittedwith resilient means, may be used in place of the cups 43 to accommodateother types of electronic tubes. Electrical leads 45 from the apparatus(not shown) in the container are soldered or otherwise connected to thelower ends of the rods 2i and the cups 4I.

To use the type of container, shown in Figures l and 2, the metal box iland the glass cover i3, with the metal fittings 30 and 43 bondedtherein, are prefabricated. The user need but mount the electronic orother apparatus (not shown) within the box ii, attach electrical leads45 from said apparatus to the` rods 3| and cups 43, position the coveri3 upon the flange I9 and box II may be made of sheet metal, all of thejoined edges being hermetically closed as by Y welding or soldering.'Ihe cover I3 is made from a single piece of glass molded to shape. Thepas-l sages 29 and bores 39 may be left in the molding or may be drilledthrough the glass thereafter. The upper ends of the upwardly extendingprotuberances 21 and the chamfered surfaces 4I are then silvered forsoldering by one of the conventional processes.

The rods 3I are positioned with the sheaths 33 and are hermeticallysealed therein by welding, soldering or other suitable processing toform the lead-through conductors 30, or said conductors may be made upentirely of a single piece of metal. The cups 43 are then placed Withinthe bores 39 and are bonded to the silvered chamfered surfaces 4I bymeans of solder 2|. lThe conductors may then be positioned in thepassages 29 and. while the glass cover I3 is held in an invertedposition, the silvered surfaces of the glass protuberances 21 are bondedto the hood-like metal flanges by solder 2 I.

Should the soldering of the conductors 30 or cups 43 to the glass coverI3, or the soldering of the said glass cover I3 to the box II provediilicult, due to lack of room, soldering by induction heating may beadvantageously utilized. The solder 2| will flow in the wedge-likechannel, between the inner walls I1 and the peripheral edge of the coverI3, andwill be kept from running into the interior of the box II by theilanges I9. and will result in an excellent, hermetic seal and a goodmechanical joint.'

It is to be noted that the conductors 30, which may be subjected toexternal bending and stresses, are elongated and pass through arelatively thick portion of the glass so as to better stand upmechanically under abuse. The tube cups 43, however, which will probablynot be subjected to nearly as much physical strain, may be safelypositioned in relatively thinner portions of the glass.

As the glass cover I3 comprises an entire wall of the container, theopening into which it ts is large enough to expedite positioning andmounting of apparatus within the container and to fasten electricalleads 45 from said apparatus to the rods 3| and cups 43. The foldbetween the walls I5 and the angulated inner walls I1 allows thermalhorizontal expansion and contraction of the glass cover I3 relative tothe walls, as will occur if the coefficients of expansion of the twomaterials used are different, it being preferred, of course, to choosematerials having the same or similar coefficients whenever possible.

The undulations in the upper and lower surfaces of the glass cover I3,resulting from the beading 23, the protuberances 21 and the mound 31increase the lengths of the possible surface leakage paths between theconductors 30, the cups 43, and the metal walls I5. This construction isintended to reduce the likelihood of electrical leakage and arcingbetween conductors, which has been found to occur all too often withconventional container construction. Such lengthening of the leakagepaths is more important on the upper surface of the glass cover I3,where conditions may vary greatly, than on the lower hermetically sealedin surface, where conditions are subject to more control and to far lessvariation.

The' container illustrated in Figures 3, 4 and 5 is shown as used for atype of transformer tuned by varying the longitudinal position of a slug`(of iron filings) within the transformer coils. Such containercomprises a one piece glass spool 41 and a tubular glass cover 53. Thespool 41 consists of a tubular core 49 and two circular end flanges 5I,disposed at right angles to said core. At several points, near the outerperiphery of one or both of the end flanges 5I, are 'apertures 59 whichhave chamfered surfaces 6I at their outer ends. Through each of saidapertures 59 is disposed a solid metal lead-through conductor 63, bondedto the chamfered surface 6I by means of solder 2I, as shown particularlyin Figure 5. Transformer coils 55 are wound about the spool 41 up toabout the level indicated by the broken lines and their leads 51 areconnected to the inner ends of the conductors 63 by solder or in anyother conventional manner. vThe tubular glass cover 53 is then slippedover the spool 41 and its inner peripheral surfaces B8, at both ends,are bonded respectively to the outer peripheral edges 66 of the endflanges 5I, by solder 2I as already mentioned, so as to hermeticaliyenclose the coils Slidably disposed within the tubular core 49 is acylindrical slug 65 which is secured to the end of a rod 61. Thetransformer may be tuned by moving the slug 65 longitudinally by meansof the rod 61 without in any way interfering with the hermeticallysealed container or the coils 55 therewithin.

The container just described, and shown in Figures 3, 4, and 5, may beprefabricated in two separate parts, the tubular glass cover 53 beingone, and the glass spool 41 with the lead-through conductors 93 alreadybonded in place being the other. The outer peripheral edges 66 of theend anges 5I and the inner peripheral surfaces 68 at both ends of thetubular cover 53 should also be presilvered as already mentioned. Theuser of such a prefabricated container need then but wind thetransformer coils 55 about the spool 41, connect the leads 51 from saidcoils to the conductors E3, move the cover 53 into place and solder itto the spool.

It is to be understood that in this type of container the glass may bethickened to accommodate the lead-through conductors and the glass mayalso have various undulations for strength and increased leakage pathsas already shown and described in connection with Figures 1 and 2. Thistype of container, wherein the two members are of the same material,need not have means to equalize differences in thermal expansion.

Referring now to Figures 6 and 7, there is I shown a hermetically sealedcontainer for a selenium rectifier BI or the like. The containercomprises a hollow glass cylinder 69 and two metal end caps 1I. Theglass cylinder 69 is provided with two outwardly extending integralbeadings 13, which respectively are set in a short distance from theends of the cylinder, and a suitable number of lead-through conductors30 (two being shown) positioned intermediate said headings 13. Theconductors 30 shown are of the same type as those already described inconnection with Figures 1 and 2. Each comprises a rod 3| and a tubularsheath 33, with a hood-like flange 35, which rod and sheath pass througha passageway 29 extending through upwardly and downwardly directedprotuberances 21 in the glass cylinder 59.

Each end cap 1I is made up of sheet metal and comprises a circular disk15, the perimetric portion of which if folded over and inwardly and thenin a. direction normal to the plane of the disk, so as to form acylindrical rim 11, which rim is of a size to telescope over one end ofthe V.glass cylinder 89. A mounting bracket 18 of suitable type may beattached to the rim 11 of each of the end caps 1|. Said rims 11 arebonded to the glass-cylinder 68 by means of solder 2| so as tohermetically seal the two end caps 1| to the glass cylinder and therebyseal the ap paratus 8| within the container.

The two end caps 1|, with the mounting brackets integral therewith orattached thereto, and the cylinder 88 with the lead-through con- Yductors 30 bonded in place and the outer peripheral portions silvered,may be prefabricated.

In use, the apparatus 8| to be housed is secured to one of the end caps1 I, as by legs 85 spot welded to the inner surface of. said end cap.Electrical leads 83 from the apparatus 8| are then joined to the innerends of the lead-through conductors 30 in the glass cylinder 69, saidapparatus being held partly within one end of the glass cylinder during.said operation so as to keep the leads as short as possible. The end cap1|, to which the apparatus 8| is secured, is then bonded to the cylinder69 by solder 2| between the inner surface of the rim 11 and the outerperipheral surface of one end of the glasscylinder. The second end cap1| is then similarly bonded to the other end oi the cylinder 69. Theconstruction of the container shown in Figures 6 and 7 is such as toallow materials of slightly different expansion coeilicients to be used,as the folded over peripheral edges of the end caps 1| will absorbdiiferences in expansion between the two materials. V

If desired, this type of container may have one of the end caps 1|bonded to one end of the cylinder 89 during prefabrication. Then theconnecting of the leads 83 and the inserting of the apparatus 8| areboth accomplished through the other end of the cylinder 69, resultingusuallyin slightly longer leads.

The invention herein may also be applied to containers f or coils orother apparatus, which are provided with a plurality of parallel prongsfor insertion into a standard socket. In such applisimilar vitreousmaterials are largely referred to` herein, other insulating materialsmay be used in utilizing the invention here set forth. For instance, itis understood that certain plastics and pressed materials have beendeveloped which may be processed so that they may be readily and simplybonded to metal or other materials as by soldering. Containers, madeaccording to the present invention, may use some of these materials forthe insulating wall or panel housing the terminals and also for thebalance of the container.

Ii it is desired to evacuate or pressurize any of the containersdescribed in this speciilcation, or introduce gas therein, a suitableopening or nipple for this purpose, according to conventional practice,may be left in the insulating material, said opening to be hermeticallysealed when it has served its purpose.

While several illustrative embodiments of the present invention havebeen described, it will be obvious that various modifications may bemade without departing fromthe spirit of the invention.

We claim:

A container for an apparatus comprising a metal box open substantiallythroughout one entire side, the peripheral edges of the box about saidopen side being folded over to form an inner wall extending entirelyaround said open side, said inner wall being spaced slightly from theouter wall of said box and being slightly angulated thereto, a ilangeextending inwardly from said inner wall and completely around said openside so as to form a supporting ledge, a glass cover adapted to fit andclose said open side and have its periphery abut said inner wall andhave its inner surface rest against said supporting ledge, a hermeticseal of solder between the periphery of 4,0 the glass cover and theinner wall to completely cation at least one end of the container may be50 made of a single piece of glass or other insulating material having aplurality of suitably positioned lead-through conductor prongshermetically bonded therein. Said piece of insulating material ishermetically bonded to the balance oi' the 'container as alreadydescribed.

It will be understood that, although glass or close and hermeticallyseal the open side of the box aforesaid so as to form a hermeticallysealed container about said apparatus.

GEORGE R. SPARKS. CARROLL G. KILLEN, Ja.

REFERENCES CITED The following references are of record in the le ofthis patent:

- UNITED STATES PATENTS Number 2,162,489 Matthies June 13, 1939 -N ai

